Resistance unit.



W. J. LLOYD.

RESISTANCE UNIT.

APPLIOATION FILED AUG. 6, 1910.

Patented Dec. 12; 1911.

.. r!!!IllIfIIIIIIIIIIIIIIl/ ll 1 II I I II 5 6.

u m w Witnesses: 1 I

Inventor". William J.L|o d, y

Hls yitto'rneg UNITED STATES PATENT OFFICE.

WILLIAM J. LLOYD, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

RESISTANCE UNIT.

Specification of Letters Patent.

Patented Dec. 12, 1911.

Application filed August 6, 1910. Serial No, 575,964.

citizen of the United States, residing at Lynn, county of Essex, State of Massachusetts, have invented certaln new and useful Improvements in Resistance Units, of which the following is a specification.

My invention relates to a resistance unit particularly adapted for use in electric meters.

In electric meter construction compactness and light weight are highly desirable features, and in fact are frequently essential to the commercial success of measuring instruments, but these characteristics are incorporatcd with difliculty in resistance units by reason of the fact that they are usually diametrically opposed to good heat radia tion and good insulation.

I propose by my invention to design a unit that is characterized both by its compactness and light weight and its good heat radiation and insulation.

Further advantages of my invention consist in the construction and assembly of a resistance unit in such a manner that it is inexpensive to manufacture and easily assembled or disassembled, and is rigid in construction.

For a better understanding of the novelty and advantages of my invention, reference may be had to the accompanying drawing .and the description of the same.

fastened, respectively, to the two ends of resistance 2 at 5, 5 in any well known manner, and passlng around the end surfaces of the tube 1 to the interior thereof aresoldered to the ends of the conductors 3, 3.

tube 1 through the central longitudinal openings of bushings 6, 6 and these openings have flaring or bell shaped mouths so as not to' abrade the insulation of said. conductors. I

On the outer surfaces of bushin s 6,-6 are formed longitudinal serrations 6 (only one of which is shown) extending backwardly from shoulders 7 to the ends of the bushings for the passage therethrough of con ducting strips 4, 4 to the interior of the tube. An outer casing 8, preferably perforated to permit of ventilation, surrounds the resistance tube 1 and is'slightly longer and of a larger diameter than the same but is maintained concentric therewith by means of suitable heads both of which are preferably removable, such as the screw heads 9, 9 which screw on the ends of said casing and have central openings for fitting snugly over the outer ends of bushings 6, 6, as shown. Around the circumferences of these central openings are formed integrally therewith sleeves 10 (only one of which is visible) which frictionally engage with shoulders 7 when the heads are screwed on casing 8, the bushings 6, 6 thereby being held securely in position with their shoulders 7 resting against the ends of the tube 1.

The whole unit is supported by bent arms 11 which are secured to the casing 8 by rivets, as shown, and at their free ends have holes 12 in order that they maybe secured to the meter framework. Knots 13 are formed in the conductors 3, 3-inside the tube in such a manner that they cannot pass through the openings in bushings G, 6 but rest against the 111116]? end surfaces of said bushings, thereby preventing mechanr cal strain upon the-soldered joints between conductors 3, 3 and strips l, 41-.

To disassemble this resistance unit, it is only necessary to unscrew one head from the casing; the casing, being larger in diameter than the tube and bushings, will pass longitudinally over them. After the heads are removed, the bushings 6, 6 may be taken out of the tube and access had to the inner part of the latter.

What I claim as new and desire to secure by Letters Patent of the United States, is,-

1. A resistance unit comprising an insulating tube having resistance wire coiled therearound, an insulating bushing in each end of said tube for supporting the same, an outer perforated casing of larger diamlating tube having resistance wire coiled "held concentric with said tube by means ings in position.

with saidshoulders so as to lock said busheter than said tube, and means for holding said casing concentric therewith comprising heads shaped to fit the outer surface of said bushin s. and removably secured to the ends of sai outer casing.

2. =A resistance unit comprising an insutherearound, an insulating bushing in each end of said tube for supporting the' same having a shoulder of larger diameter than said tube, and an outer perforated casing of heads removably secured to the ends of said casing, said heads frictionally engaging with said shoulders and locking said bushingsin position, and flexible conductors for passing through said bushings to the interior of said tube and having knots formed therein rcstin against the inner end surfaces of said bushings for the purpose set forth.

4. A resistance unit comprising an insulating tube having resistance wire coiled therearound, an insulating bushing in each end of said tube for supporting the same having a shoulder of larger diameter than said tube, an outer cylindrical perforated casing held concentric with said tube by means of screw heads screwing on the .ends of said casing and frictionally engaging with said shoulders so as to lock said bushings in position, flexible conducting strips secured to said resistance terminals and.

passing around the end surfaces of said tube to the interior thereof through serrations on the outer surfaces of said bushings, and flexible conductors passing through said bushings for connecting on the ends of said strips and having knots formed therein rest ing against the inner ends of said bushings. In witness whereof, I have hereunto set my'hand this fourth day of August, 1910.

WILLIAM J. LLOYD.

Witnesses:

DUGALD MoK. MCKILLOP, CHARLES A. BARNARD.

Copies of this patient may be obtained for flve cents each, by addressing the Commissioner of Patents, Washington, D. G. 

